Re: I'd go with the nVidia Shield TV
I've got a Shield as well, and it's everything I could want in a set top box, apart from the app support due to it being Android TV, vs Android. But Roku doesn't even run that, and has it's own shop which limits it's ecosystem also.
I'd take my shield every day of the week, but the new Telstra TV which is based on the Roku Ultra with FTA reception and app intergration between FTA app, EPG and FTA reception, as attracted my attention. It also comes with Foxtel (local PayTV) and NetFlix support. Disappointed though it only has 100Mbit ethernet, and even then doesn't support PoE for it's low power consumption.